Field of the Invention
Embodiments of the present invention relate to a printed circuit board and a method of manufacturing the same, and more specifically, to a printed circuit board which can be used as a substrate for a package, a method of manufacturing the printed circuit board, and a semiconductor package using the printed circuit board.
Related Arts
A package on package (hereinafter referred to as “POP”) is a packaging technology for laminating another package substrate on a printed circuit board or a package substrate. The conventional FC POP (Flip Chip Package on Package) has a form in which a top package for mounting a general memory chip and a bottom package for mounting a processor chip are laminated in a flip chip method. This POP technology is advantageous in that a mounting area can be reduced by forming a processor chip and a memory chip as one package assembly and a high speed signal transmission can be performed by a short path. Thanks to these advantages, the POP technology has been frequently applied to mobile devices.
Also, the FC POP technology may be classified into an SBA (Solder Ball Attach) method using a solder ball for an POP connection and a TMV (Through Mold Via) method to which a laser technology is applied. As various mobile devices have been diversified and miniaturized, a POP pitch has been also reduced to a remarkably minute size. In this trend, the conventional SBA method is disadvantageous in that short defects are high due to the generation of a bridge between solder balls in the fine pitch. Accordingly, since the SBA method has a low yield rate in a process under the condition of about 500 μm or less in a pitch size, it cannot be used in the process. Also, the conventional TMV method is disadvantageous in that it cannot be used in a process under the condition of about 400 μm or less in a pitch size for the same reason.
In addition, in the conventional FC POP technology, a bump solder is used as a package bump for supporting the bottom package and the top package. When this solder bump is used, a size of the solder bump cannot be increased beyond a fixed size due to the occurrence of a solder bridge resulting from a limited chip size. Accordingly, it is disadvantageous in that a degree of freedom in design with a spaced distance between packages required in a semiconductor package is limited.